Administration of blood components--avoiding unnecessary costs.

Blood components must be transfused through a sterile, pyrogen-free transfusion set which has an in-line filter (170 μm pore size), drip chambers and tubing. The filter serves to remove potentially harmful clots and debris that may have formed during collection or storage. Although the Transfusion Services carefully inspect individual units before issuing, there is a slight chance that a small clot could go undetected and hence this filter is recommended for the administration of all components. The cost of the set is approximately R30. It should be emphasised that the chances of clot formation during storage are very low since red cells are mainly prepared as buffy coat-poor concentrates mixed with an additive solution and anticoagulant and contain very little plasma and are relatively depleted of white cells and platelets. Most manufacturers recommend that the set be changed after 24 hours or following a specified number of units. Trapped protein and debris provide a potential medium for bacterial growth; also, as filtered particles accumulate, the flow rate decreases. Platelets are given using a set containing a 170 μm filter although the surface area of the filter is smaller than that used for red cells. Fresh-frozen plasma and cryoprecipitate are also best given through this standard administration set in case small fibrin strands are present.